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using System;
using System.IO;
using System.Text;
using Org.BouncyCastle.Asn1;
using Org.BouncyCastle.Asn1.X509;
using Org.BouncyCastle.Crypto.Digests;
using Org.BouncyCastle.Crypto.Macs;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Utilities;
using Org.BouncyCastle.Utilities.Date;
using Org.BouncyCastle.Utilities.IO;
namespace Org.BouncyCastle.Crypto.Tls
{
/// <remarks>Some helper functions for MicroTLS.</remarks>
public class TlsUtilities
{
internal static void WriteUint8(byte i, Stream os)
{
os.WriteByte(i);
}
internal static void WriteUint8(byte i, byte[] buf, int offset)
{
buf[offset] = i;
}
internal static void WriteUint16(int i, Stream os)
{
os.WriteByte((byte)(i >> 8));
os.WriteByte((byte)i);
}
internal static void WriteUint16(int i, byte[] buf, int offset)
{
buf[offset] = (byte)(i >> 8);
buf[offset + 1] = (byte)i;
}
internal static void WriteUint24(int i, Stream os)
{
os.WriteByte((byte)(i >> 16));
os.WriteByte((byte)(i >> 8));
os.WriteByte((byte)i);
}
internal static void WriteUint24(int i, byte[] buf, int offset)
{
buf[offset] = (byte)(i >> 16);
buf[offset + 1] = (byte)(i >> 8);
buf[offset + 2] = (byte)(i);
}
internal static void WriteUint64(long i, Stream os)
{
os.WriteByte((byte)(i >> 56));
os.WriteByte((byte)(i >> 48));
os.WriteByte((byte)(i >> 40));
os.WriteByte((byte)(i >> 32));
os.WriteByte((byte)(i >> 24));
os.WriteByte((byte)(i >> 16));
os.WriteByte((byte)(i >> 8));
os.WriteByte((byte)i);
}
internal static void WriteUint64(long i, byte[] buf, int offset)
{
buf[offset] = (byte)(i >> 56);
buf[offset + 1] = (byte)(i >> 48);
buf[offset + 2] = (byte)(i >> 40);
buf[offset + 3] = (byte)(i >> 32);
buf[offset + 4] = (byte)(i >> 24);
buf[offset + 5] = (byte)(i >> 16);
buf[offset + 6] = (byte)(i >> 8);
buf[offset + 7] = (byte)(i);
}
internal static void WriteOpaque8(byte[] buf, Stream os)
{
WriteUint8((byte)buf.Length, os);
os.Write(buf, 0, buf.Length);
}
internal static void WriteOpaque16(byte[] buf, Stream os)
{
WriteUint16(buf.Length, os);
os.Write(buf, 0, buf.Length);
}
internal static void WriteOpaque24(byte[] buf, Stream os)
{
WriteUint24(buf.Length, os);
os.Write(buf, 0, buf.Length);
}
internal static void WriteUint8Array(byte[] uints, Stream os)
{
os.Write(uints, 0, uints.Length);
}
internal static void WriteUint16Array(int[] uints, Stream os)
{
for (int i = 0; i < uints.Length; ++i)
{
WriteUint16(uints[i], os);
}
}
internal static byte ReadUint8(Stream inStr)
{
int i = inStr.ReadByte();
if (i < 0)
{
throw new EndOfStreamException();
}
return (byte)i;
}
internal static int ReadUint16(Stream inStr)
{
int i1 = inStr.ReadByte();
int i2 = inStr.ReadByte();
if ((i1 | i2) < 0)
{
throw new EndOfStreamException();
}
return i1 << 8 | i2;
}
internal static int ReadUint24(Stream inStr)
{
int i1 = inStr.ReadByte();
int i2 = inStr.ReadByte();
int i3 = inStr.ReadByte();
if ((i1 | i2 | i3) < 0)
{
throw new EndOfStreamException();
}
return (i1 << 16) | (i2 << 8) | i3;
}
internal static void ReadFully(byte[] buf, Stream inStr)
{
if (Streams.ReadFully(inStr, buf, 0, buf.Length) < buf.Length)
throw new EndOfStreamException();
}
internal static byte[] ReadOpaque8(Stream inStr)
{
byte length = ReadUint8(inStr);
byte[] bytes = new byte[length];
ReadFully(bytes, inStr);
return bytes;
}
internal static byte[] ReadOpaque16(Stream inStr)
{
int length = ReadUint16(inStr);
byte[] bytes = new byte[length];
ReadFully(bytes, inStr);
return bytes;
}
internal static void CheckVersion(byte[] readVersion)
{
if ((readVersion[0] != 3) || (readVersion[1] != 1))
{
throw new TlsFatalAlert(AlertDescription.protocol_version);
}
}
internal static void CheckVersion(Stream inStr)
{
int i1 = inStr.ReadByte();
int i2 = inStr.ReadByte();
if ((i1 != 3) || (i2 != 1))
{
throw new TlsFatalAlert(AlertDescription.protocol_version);
}
}
internal static void WriteGmtUnixTime(byte[] buf, int offset)
{
int t = (int)(DateTimeUtilities.CurrentUnixMs() / 1000L);
buf[offset] = (byte)(t >> 24);
buf[offset + 1] = (byte)(t >> 16);
buf[offset + 2] = (byte)(t >> 8);
buf[offset + 3] = (byte)t;
}
internal static void WriteVersion(Stream os)
{
os.WriteByte(3);
os.WriteByte(1);
}
internal static void WriteVersion(byte[] buf, int offset)
{
buf[offset] = 3;
buf[offset + 1] = 1;
}
private static void hmac_hash(IDigest digest, byte[] secret, byte[] seed, byte[] output)
{
HMac mac = new HMac(digest);
KeyParameter param = new KeyParameter(secret);
byte[] a = seed;
int size = digest.GetDigestSize();
int iterations = (output.Length + size - 1) / size;
byte[] buf = new byte[mac.GetMacSize()];
byte[] buf2 = new byte[mac.GetMacSize()];
for (int i = 0; i < iterations; i++)
{
mac.Init(param);
mac.BlockUpdate(a, 0, a.Length);
mac.DoFinal(buf, 0);
a = buf;
mac.Init(param);
mac.BlockUpdate(a, 0, a.Length);
mac.BlockUpdate(seed, 0, seed.Length);
mac.DoFinal(buf2, 0);
Array.Copy(buf2, 0, output, (size * i), System.Math.Min(size, output.Length - (size * i)));
}
}
internal static byte[] PRF(byte[] secret, string asciiLabel, byte[] seed, int size)
{
byte[] label = Strings.ToAsciiByteArray(asciiLabel);
int s_half = (secret.Length + 1) / 2;
byte[] s1 = new byte[s_half];
byte[] s2 = new byte[s_half];
Array.Copy(secret, 0, s1, 0, s_half);
Array.Copy(secret, secret.Length - s_half, s2, 0, s_half);
byte[] ls = Concat(label, seed);
byte[] buf = new byte[size];
byte[] prf = new byte[size];
hmac_hash(new MD5Digest(), s1, ls, prf);
hmac_hash(new Sha1Digest(), s2, ls, buf);
for (int i = 0; i < size; i++)
{
buf[i] ^= prf[i];
}
return buf;
}
internal static byte[] PRF_1_2(IDigest digest, byte[] secret, string asciiLabel, byte[] seed, int size)
{
byte[] label = Strings.ToAsciiByteArray(asciiLabel);
byte[] labelSeed = Concat(label, seed);
byte[] buf = new byte[size];
hmac_hash(digest, secret, labelSeed, buf);
return buf;
}
internal static byte[] Concat(byte[] a, byte[] b)
{
byte[] c = new byte[a.Length + b.Length];
Array.Copy(a, 0, c, 0, a.Length);
Array.Copy(b, 0, c, a.Length, b.Length);
return c;
}
internal static void ValidateKeyUsage(X509CertificateStructure c, int keyUsageBits)
{
X509Extensions exts = c.TbsCertificate.Extensions;
if (exts != null)
{
X509Extension ext = exts.GetExtension(X509Extensions.KeyUsage);
if (ext != null)
{
DerBitString ku = KeyUsage.GetInstance(ext);
int bits = ku.GetBytes()[0];
if ((bits & keyUsageBits) != keyUsageBits)
{
throw new TlsFatalAlert(AlertDescription.certificate_unknown);
}
}
}
}
}
}
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